Testosterone therapy may not improve sexual function or quality of life in men with lower levels of the sex hormone, researchers, including one of Indian-origin, have found.
The three-year study from Brigham and Women's Hospital (BWH) in US found that testosterone administration had no effect on the progression of hardening of the arteries in older men with low to low normal testosterone levels and did not significantly improve sexual function or health-related quality of life.
"The results of this trial suggest that testosterone should not be used indiscriminately by men," said corresponding author Shalender Bhasin, director of BWH's Research Programme in Men's Health: Ageing and Metabolism.
"We find that men with low and low normal testosterone are unlikely to derive benefits in terms of sexual function or quality of life, two reasons why men may seek testosterone therapy," Bhasin said.
"And although we find that testosterone did not affect the rate of hardening of the arteries, we need long-term data from large trials to determine testosterone's effects on other major cardiovascular events," he said.
Testosterone, a hormone primarily secreted by the testicles, plays a key role not only in male reproductive tissues but also in muscle growth, bone mass and body hair.
As men get older, their testosterone levels naturally decline - on average by one per cent a year after age 40.
The research team enrolled more than 300 men over the age of 60 with total testosterone levels between 100-400 nanograms per decilitre (ng/dL) (low to low normal range) and measured two indicators of atherosclerosis: calcium deposits in the arteries of the heart (coronary artery calcification) and the thickness of inner lining of the carotid arteries that supply blood to the brain (common carotid artery intima-media thickness).
To measure secondary outcomes of sexual function and health-related quality of life, the research team had participants also completed a 15-item questionnaire.
Participants applied a testosterone or placebo gel daily for three years.
"Many men, as they get older, experience a decline in testosterone and in sexual function and vitality. But our study finds that taking testosterone, when levels are in the low to low normal range, may not improve sexual function or quality of life," Bhasin added.
The study was published in the Journal of the American Medical Association (JAMA).
